How Utah counties monitor pollution in the air during bad inversion spells

SALT LAKE CITY -- One look outside and it is obvious. Utah has been dealing with another inversion, trapping pollution in the bottom of the valleys.

“The thermal inversions set up a little differently everywhere,” said Jared Mendenhall, a Utah DEQ Spokesman.

However, the warning you find on the Utah Air app or Utah DEQ website is typically based on just one monitoring station in each county.

“When you look at either air.utah.gov or the Utah Air app, you’re seeing for Salt Lake City, you’re seeing the Hawthorne monitor,” said Mendenhall.

The Hawthorne station is just south of Liberty Park at Hawthorne Elementary School. Though it is the standard for setting warnings for Salt Lake County, there are actually hundreds of monitors spread out in just about every neighborhood, collecting data on pollution levels block-by-block.

“It varies quite a lot. That’s the real value of having these low-cost sensors,” said Erik Crosman Ph.D., a climate researcher at the University of Utah. “It’s very useful information to see qualitatively are you in a polluted area because sometimes some parts of the valley may be clean and other parts may be polluted.”

The network of sensors is useful but Crosman warns they quality of the data they gather can be thrown off.

“If it’s humid or foggy, you could be getting a number from one of the low-quality sensors that is four or five times higher than what it actually is,” said Crosman.

While you may not want to rely on the exact numbers coming from each sensor, Crosman believes having a wide network of monitors can be extremely useful in tracking pollution.

“To get a sense of where are the most polluted areas and where are the least polluted areas, then all of the sensors should be used,” said Crosman.